Alpha S1 Research Articles

Regulation of the expression of casein alpha S1 and S2 genes in the bovine mammary epithelial cells by STAT5A

Cow milk is rich in protein. Major cow milk proteins include casein α S1 (CSN1S1), casein α S2 (CSN1S2), casein β (CSN2), casein kappa (CSN3), lactalbumin α (LALBA), and β-lactoglobulin (LGB). These milk proteins are produced through gene expression in the mammary epithelial cells. Little is known about the molecular mechanism that mediates the expression of milk protein genes in cows. In this study, we tested the hypothesis that the expression of milk protein genes in cows is mediated by STAT5A, a transcription factor that is induced to bind and activate the transcription of target genes by extracellular signals such as prolactin. To circumvent the need of prolactin-responsive bovine mammary epithelial cells, we generated a plasmid that expresses a constitutively active bovine STAT5A variant, bSTAT5ACA. Transfection of the bovine mammary epithelial cell line MAC-T cells with the bSTAT5ACA expression plasmid caused a more than 100,000-fold and 600-fold increase in the expression of CSN1S1 and CSN1S2 mRNAs, respectively, compared with transfection of the wild-type bovine STAT5A (bSTAT5A) expression plasmid. Transfection of bSTAT5ACA, however, had no significant effect on the expression of CSN2, CSN3, LALBA, or LGB mRNA in MAC-T cells. Transfection of bSTAT5ACA caused a more than 260-fold and 120-fold increase in the expression of a luciferase reporter gene linked to the bovine CSN1S1 and CSN1S2 promoters in MAC-T cells, respectively, compared with that of bSTAT5A. The bovine CSN1S1 and CSN1S2 promoters each contain a putative STAT5 binding site, and gel-shift and super-shift assays confirmed bSTAT5ACA binding to both sites. These results together suggest that STAT5A plays a major role in regulating the expression of CSN1S1 and CSN1S2 genes in the bovine mammary epithelial cells and that STAT5A regulates the expression of these genes at least in part by binding to the STAT5 binding sites in their promoter regions. These results also suggest that STAT5A does not play a major role in regulating the expression of other major milk protein genes.

Molecular Characteristics of JAK2 and Its Effect on the Milk Fat and Casein Synthesis of Ovine Mammary Epithelial Cells.

In addition to its association with milk protein synthesis via the Janus kinase-signal transducer and activator of transcription (JAK-STAT) pathway, JAK2 also affects milk fat synthesis. However, to date, there have been no reports on the effect of JAK2 on ovine mammary epithelial cells (OMECs), which directly determine milk yield and milk contents. In this study, the coding sequence (CDS) region of ovine JAK2 was cloned and identified and its tissue expression and localization in ovine mammary glands, as well as its effects on the viability, proliferation, and milk fat and casein levels of OMECs, were also investigated. The CDS region of ovine JAK2, 3399 bp in length, was cloned and its authenticity was validated by analyzing its sequence similarity with JAK2 sequences from other animal species using a phylogenetic tree. JAK2 was found to be expressed in six ovine tissues, with the highest expression being in the mammary gland. Over-expressed JAK2 and three groups of JAK2 interference sequences were successfully transfected into OMECs identified by immunofluorescence staining. When compared with the negative control (NC) group, the viability of OMECs was increased by 90.1% in the pcDNA3.1-JAK2 group. The over-expression of JAK2 also increased the number and ratio of EdU-labeled positive OMECs, as well as the expression levels of three cell proliferation marker genes. These findings show that JAK2 promotes the viability and proliferation of OMECs. Meanwhile, the triglyceride content in the over-expressed JAK2 group was 2.9-fold higher than the controls and the expression levels of four milk fat synthesis marker genes were also increased. These results indicate that JAK2 promotes milk fat synthesis. Over-expressed JAK2 significantly up-regulated the expression levels of casein alpha s2 (CSN1S2), casein beta (CSN2), and casein kappa (CSN3) but down-regulated casein alpha s1 (CSN1S1) expression. In contrast, small interfered JAK2 had the opposite effect to JAK2 over-expression on the viability, proliferation, and milk fat and milk protein synthesis of OMECs. In summary, these results demonstrate that JAK2 promotes the viability, proliferation, and milk fat synthesis of OMECs in addition to regulating casein expression in these cells. This study contributes to a better comprehension of the role of JAK2 in the lactation performance of sheep.

Comparative Protein Profiling of Blood and Milk of Early Pregnant Buffaloes Using SDS-PAGE

Conventional methods for detecting pregnancy in buffalo are inefficient before 30-days after artificial insemination. A proteomic approach for high-resolution analysis of blood plasma and milk proteins by SDS polyacrylamide gel electrophoresis (PAGE) is of great importance. Blood and milk samples were collected on days 0 (before insemination) and 20 and 25 after insemination from retrospective pregnant (n = 6) and non-pregnant (n = 6) animals. An equal volume of samples was loaded in (12%-4%) SDS gel to resolve major plasma and milk proteins. Plasma proteins showed three distinct zones – high, medium, and low molecular weight (MW). In the high MW zone (135 - 250 kDa), ~208 kDa and ~190 kDa proteins were visible. In the moderate MW zone (60 -75 kDa), 5-6 proteins like albumin (~70 kDa), 75 kDa, and 63 kDa consisting of pregnancy-associated glycoproteins, ~73 kDa being dominant. In the low MW zone (25 – 35 kDa), a clear band of 27 kDa was visible. Proteins in milk supernatants showed four distinct zones of proteins – very high, high, medium, and low molecular weight (MW) zones. In the very high MW zone (135 - 250 kDa), ~208 kDa and ~190 kDa proteins were visible. In the high MW zone (60 -75 kDa), proteins like lactoferrin (~78.2 kDa), 73 kDa, albumen (~66 kDa), and a heavy chain of immunoglobulin (IgG) (~54 kDa) were detected. In the medium MW zone (25 – 35 kDa), clear bands of milk caseins, namely thick alpha S2 casein (29 kDa), and other caseins. In the low MW zone (11 – 20 kDa), two thick bands of 18 kDa and 12 kDa were visible. The mean gray values (sum of the gray values of all the pixels in the peak divided by the number of pixels) of the 73 kDa protein peak were analyzed in two-way ANOVA using GraphPad (ver 8.0). Repeated measures of ANOVA were selected where pregnancy status (pregnant and non-pregnant) defined column factor and time (0-, 20- and 25-day) defined row factor. The expression of 73 kDa protein in blood plasma was higher (P = 0.04) in pregnant women than in non-pregnant buffaloes at 20- and 25-days after insemination. However, in milk, there was no difference in the expression of the 73 kDa protein between pregnant and non-pregnant buffaloes across time. Variation in animals within the groups was significantly high. The differential expression of ~73 kDa protein in plasma and precise identification of the protein can be a diagnostic marker for early pregnancy detection in buffaloes.

Molecular characterization of buffalo αs1-casein gene

The caseins (Alpha s1, Alpha s2, beta and kappa) comprise the major protein component of ruminant milk and are secreted in the form of stable calcium phosphate micelles. The present study was proposed to characterize αs1-casein gene in buffalo at the molecular level to determine complete αs1-casein cDNA sequence. Sequencing results were analyzed and aligned with available mRNA GenBank sequences of other domestic animals (Accession AAB34797, NM_001009795, X72221, AY344966, NM_181029, AY948385 and BC109618). The complete amino acid coding region of the buffalo αs1- casein was deduced from cloned cDNA generated from mammary tissue mRNA. Amino acid sequence comprises of 199 amino acid residues. When aligned with previously reported buffalo sequence (Accession-AY948385) it showed one amino acid (Glutamine) deletion at amino acid position 78.

The Occurrence of CSN1S1 E Allele on Saanen Goat Population at BBPTU-HPT Baturraden

The CSN1S1 gene is expressed as the milk alpha S1 casein which is valuable for cheese making. Allele E is a mutation of this gene, which is correlated with low quantity of expressed protein. This study aimed to identify the occurrence of CSN1S1 E allele on the Saanen population at BBPTU-HPT Baturraden. Blood samples of 45 does were drawn, followed by DNA isolation using the column spin method. The identification of E allele was carried out by Allele Specific Polymerase Chain Reactions (AS-PCR) with forward primer 5-TCAGGAGCAGTGGGTATGTG-3 and reverse 5-CCTCCCAATGGAATAATGACA-3. Allele E was found as heterozygote genotype with non-E allele in 28 out of 45 samples. This means that F allele frequency was 0.31 and 0.6 for non-E allele. There was no significant difference of milk protein in both groups. In summary, E allele was found in the Saanen goat population in BBPTU HPT Baturraden with no effect on milk protein production.
 Keywords: Saanen, CSN1S1, milk, goats, protein.

The Effect of Alpha s1 Genotype on Some Physiological and Chemical Milk Characteristics in Garganica Goat

In the present study individual milk samples were collected from 80 Garganica goats and the population was genotyped for CSN1S1. Seven different alleles were observed with the A allele found as predominant, followed by the F and B allele, and 14 different genotypes were observed. A proteomic approach was used to classify the individual milk on the basis of protein abundance: four levels of αs1-casein (CN) expression were identified as high (HAS-1), intermediate (IAS-1), low (LAS-1), and null (NAS-1). The present paper aimed to investigate the influence of the level of expression of αs1-casein fraction in milk on proteolytic activities, chemical composition, and renneting properties of individual Garganica goat milk. Results from the present study evidenced that the level of expression of αs1-casein fraction in Garganica goat milk affected chemical composition, curd firmness, and indigenous proteolytic enzymes. In particular, fat, protein, and casein content were higher in HAS-1 and IAS-1 compared to LAS-1 and NAS-1. The SCC decreased passing from the HAS-1 to the NAS-1 and the curd firmness displayed the highest value in HAS-1. The activity of plasmin (PL) was higher in HAS-1 and IAS-1 groups compared to the LAS-1 and NAS-1; whereas, PL plasminogen-derived (PG) activity was the highest in NAS-1 group. On the contrary, the activity of elastase was the highest in LAS-1, intermediate in the IAS-1 group, and the lowest in HAS-1 and NAS-1 groups. Present data demonstrated that the level of synthesis of αs1-CN reflects the efficiency of the mammary gland in the activation of the cellular mechanisms and influences the proteolytic activity in milk, especially the PL-PG system.

Single and combined effects of CSN1S1 and CSN2-casein genes on Awassi sheep milk quantity and quality.

Background and Aim:Milk produced from Awassi sheep is of high nutritive value; its production is relatively low in Awassi sheep, so the genetic improvement programs targeted milk production and its components are of high importance, especially when using genes that have an important signal to milk traits. This study was aimed at assessing the influence of alpha S1 (CSN1S1) and beta-casein (CSN2) genes genotypes interaction on Awassi ewes milk productivity.Materials and Methods:A total number of 391 milk yield and its composition records (taken through five consecutive years, 2007-2011) of 167 ewes were utilized for this study. DNA samples were extracted from the ewe’s blood samples, then the polymerase chain reaction products of alpha S1 (CSN1S1) and beta-casein (CSN2) genes were sequenced. The obtained sequences were analyzed; thereafter, the detected variants were tested for their possible association with milk traits.Results:The CSN1S1 and CSN2 variants allelic frequencies were 0.85 and 0.15, and 0.95 and 0.05, respectively. Lactose and solid not fat (SNF) % were associated with TC CSN1S1 genotypes. No association was found among CSN1S1 polymorphic genotypes with milk production, lactose, and SNF % were associated with TC CSN1S1 genotypes. Ewes of CSN2 AC genotype showed higher milk production traits, while no association was found between milk composition traits and CNS2 genotypes. Nevertheless, CSN1S1*CSN2 interaction showed the highest SNF, fat percentages, and milk production.Conclusion:The substantial interaction effects between CSN1S1×CSN2 genes were significantly affected the amount of milk, fat, and SNF% produced. The detected variants should be included in the breeding programs of Awassi sheep that are designed for improving their milk quantity and quality.

Heterogeneity and diversified distribution of αS2 casein variants in Indian goats

There is growing interest in goat milk and its derivatives, whose quality is essential in light of contemporary dietary trends favouring healthy eating. Goat milk is used in nutraceutical and infant food products for various reasons, including its hypoallergenic properties. Casein gene variation influences milk content and the chemical, physical, and technical aspects of goat milk. In Capra hircus, there are twelve variants of αs2 casein protein reported to date. The present study aimed to identify the polymorphism of alpha s2 casein and their transcript variants in six Indian goat breeds. Along with three reported alleles (A, B, and C), seven new alleles (L, M, N, O, P, Q, and R) were found in the six native Indian breeds. Transcript variants due to the exon skipping phenomenon were found. The novel alleles: N, P, Q, and R also represented the deletion of exon 3, 13, 6 and 6, respectively. The largest exon (exon 16) of the CSN1S2 gene was screened in 140 goats, and only one new allele, ‘S’, was found. Altogether, eight novel alleles were found in Indian goats along with two types of transcript variants.

Somatic cell score: gene polymorphisms and other effects in Holstein and Simmental cows.

ObjectiveThe aim of the study was to evaluate the influence of gene polymorphisms and nongenetic factors on the somatic cell score (SCS) in the milk of Holstein (n = 148) and Simmental (n = 73) cows and their crosses (n = 6).MethodsThe SCS was calculated by the formula SCS = log2(SCC/100,000)+3, where SCC is the somatic cell count. Polymorphisms in the casein alpha S1 (CSN1S1), beta-casein (CSN2), kappa-casein (CSN3), beta-lactoglobulin (LGB), acyl-CoA diacylglycerol transferase 1 (DGAT1), leptin (LEP), fatty acid synthase (FASN), stearoyl CoA desaturase 1 (SCD1), and 1-acylglycerol-3-phosphate O-acyltransferase 6 (AGPAT6) genes were genotyped, and association analysis to the SCS in the cow’s milk was performed. Further, the impact of breed, farm, year, month of the year, lactation stage and parity on the SCS were analysed. Phenotype correlations among SCS and milk constituents were computed by Pearson correlation coefficients.ResultsOnly CSN2 genotypes A1/A2 were found to have significant association with the SCS (p<0.05), and alleles of CSN1S1 and DGAT1 genes (p<0.05). Other polymorphisms were not found to be significant. SCS had significant association with the combined effect of farm and year, lactation stage and month of the year. Lactation parity and breed had not significant association with SCS. The phenotypic correlation of SCS to lactose content was negative and significant, while the correlation to protein content was positive and significant. The correlations of SCS to fat, casein, nonfat solids, urea, citric acid, acetone and ketones contents were very low and not significant.ConclusionOnly CSN2 genotypes, CSN1S1 and DGAT1 alleles did show an obvious association to the SCS. The results confirmed the importance of general quality management of farms on the microbial milk quality, and effects of lactation stage and month of the year. The lactose content in milk reflects the health status of the udder.

Capture Sequencing to Explore and Map Rare Casein Variants in Goats.

Genetic variations in the four casein genes CSN1S1, CSN2, CSN1S2, and CSN3 have obtained substantial attention since they affect the milk protein yield, milk composition, cheese processing properties, and digestibility as well as tolerance in human nutrition. Furthermore, milk protein variants are used for breed characterization, biodiversity, and phylogenetic studies. The current study aimed at the identification of casein protein variants in five domestic goat breeds from Sudan (Nubian, Desert, Nilotic, Taggar, and Saanen) and three wild goat species [Capra aegagrus aegagrus (Bezoar ibex), Capra nubiana (Nubian ibex), and Capra ibex (Alpine ibex)]. High-density capture sequencing of 33 goats identified in total 22 non-synonymous and 13 synonymous single nucleotide polymorphisms (SNPs), of which nine non-synonymous and seven synonymous SNPs are new. In the CSN1S1 gene, the new non-synonymous SNP ss7213522403 segregated in Alpine ibex. In the CSN2 gene, the new non-synonymous SNPs ss7213522526, ss7213522558, and ss7213522487 were found exclusively in Nubian and Alpine ibex. In the CSN1S2 gene, the new non-synonymous SNPs ss7213522477, ss7213522549, and ss7213522575 were found in Nubian ibex only. In the CSN3 gene, the non-synonymous SNPs ss7213522604 and ss7213522610 were found in Alpine ibex. The identified DNA sequence variants led to the detection of nine new casein protein variants. New variants were detected for alpha S1 casein in Saanen goats (CSN1S1∗C1), Bezoar ibex (CSN1S1∗J), and Alpine ibex (CSN1S1∗K), for beta and kappa caseins in Alpine ibex (CSN2∗F and CSN3∗X), and for alpha S2 casein in all domesticated and wild goats (CSN1S2∗H), in Nubian and Desert goats (CSN1S2∗I), or in Nubian ibex only (CSN1S2∗J and CSN1S2∗K). The results show that most novel SNPs and protein variants occur in the critically endangered Nubian ibex. This highlights the importance of the preservation of this endangered breed. Furthermore, we suggest validating and further characterizing the new casein protein variants.

The Polymorphism in Various Milk Protein Genes in Polish Holstein-Friesian Dairy Cattle.

Simple SummaryThe aim of the present study was to evaluate the genetic variability within casein alpha S1 (CSN1S1), casein alpha S2 (CSN1S2), beta-casein (CSN2), kappa-casein (CSN3), and progestagen-associated endometrial protein (PAEP) genes. The study was conducted on 1900 Polish Black and White Holstein-Friesian dairy cows that were genotyped using customized EuroGenomics microarrays. Out of investigated 24 genetic variants within four genes coding milk protein, 16 expressed genetic diversity. The fact that many of the investigated Single Nucleotide Polymorphisms (SNPs) were monomorphic may suggest that in the past the reproduction program favored one of these genotypes. Populations of high-yielding cows become more and more even and similar in terms of genotype, which may have an adverse effect in future breeding, therefore, the variability in genetic variants of genes coding milk protein should be monitored.The aim of the present study was to evaluate the genotype and allele frequencies of 24 polymorphisms in casein alpha S1 (CSN1S1), casein alpha S2 (CSN1S2), beta-casein (CSN2), kappa-casein (CSN3), and progestagen-associated endometrial protein (PAEP) genes. The study included 1900 Polish Black and White Holstein-Friesian dairy cows that were subjected to genotyping via microarrays. A total of 24 SNPs (Single Nucleotide Polymorphisms) within tested genes were investigated. Two CSN1S1 SNPs were monomorphic, while allele CSN1S1_3*G in CSN1S1_3 SNP dominated with a frequency of 99.39%. Out of seven CSN2 SNPs, four were polymorphic; however, only for CSN2_3 all three genotypes were detected. Only three out of nine SNPs within CSN3 were monomorphic. Three PAEP SNPs were also found to be polymorphic with heterozygotes being most frequent. Hardy–Weinberg equilibrium (HWE) was observed for eight variants. It was shown that only CSN3_6 was not in HWE. The fact that many of investigated SNPs were monomorphic may suggest that in the past the reproduction program favored one of these genotypes. SNPs that are included in commercially available microarrays should be monitored in relation to changes in their frequencies. If a SNP has turned monomorphic, maybe it should be considered for removal from the microarray.

Food Resources Biodiversity: The Case of Local Cattle in Slovakia

This study aimed to assess the level of biodiversity in selected local cattle populations as important food resources in Slovakia. The biodiversity level was derived from the genome-wide data collected for dairy (Jersey), dual-purpose (Slovak Pinzgau, Slovak Spotted), and beef breeds (Charolais, Limousine). The commonly used indices, genomic inbreeding (FROH, FGRM, FHOM, FUNI) and effective population size (NeLD), were used to quantify the impact of relatives mating on the genome of analysed populations. Even if the low NeLD estimates signalise significant loss of genetic variability within populations, the genomic inbreeding under 1% (except Jersey) showed that the intensity of diversity loss is not so rapid and can be managed by the re-arrangement of long-term breeding strategies. The analysis of genetic differentiation degree across populations assumed that the specialisation of breeds during their grading-up led to the specific nucleotide changes, especially in genes responsible for preferred phenotypic traits. The breed-specific differences observed mainly in the genome of Charolais (carcass traits) and Jersey (milk production traits) populations resulted from the polymorphisms in CAPN1 (μ-calpain) and CSN1S2 (casein alpha s2) genes, respectively. Obtained results confirmed that the specific haplotypes are strongly associated with the genetic nature of breed depending on production type.

Investigating the effects of transcranial alternating current stimulation on primary somatosensory cortex

Near-threshold tactile stimuli perception and somatosensory temporal discrimination threshold (STDT) are encoded in the primary somatosensory cortex (S1) and largely depend on alpha and beta S1 rhythm. Transcranial alternating current stimulation (tACS) is a non-invasive neurophysiological technique that allows cortical rhythm modulation. We investigated the effects of tACS delivered over S1 at alpha, beta, and gamma frequencies on near-threshold tactile stimuli perception and STDT, as well as phase-dependent tACS effects on near-threshold tactile stimuli perception in healthy subjects. In separate sessions, we tested the effects of different tACS montages, and tACS at the individualised S1 μ-alpha frequency peak, on STDT and near-threshold tactile stimuli perception. We found that tACS applied over S1 at alpha, beta, and gamma frequencies did not modify STDT or near-threshold tactile stimuli perception. Moreover, we did not detect effects of tACS phase or montage. Finally, tACS did not modify near-threshold tactile stimuli perception and STDT even when delivered at the individualised μ-alpha frequency peak. Our study showed that tACS does not alter near-threshold tactile stimuli or STDT, possibly due to the inability of tACS to activate deep S1 layers. Future investigations may clarify tACS effects over S1 in patients with focal dystonia, whose pathophysiology implicates increased STDT.

Differences on Biochemical Composition of GoatMilk at Carpathian Breed and Half Breed Saanen X Carpathian and French Alpine X Carpathian

The aim of our study was to evaluate the gradient of milk yield, of milk biochemical composition and fatty acids profile according to breed, for primipara goats from Carpathian breed and Saanen x Carpathian and French Alpine x Carpathian half breed that were grown in semi-intensive system (Dobrogea, South Romania). The studies were performed on goats raised at ANCC CAPRIROM farm, located in Constanta, Romania. The biochemical parameters (fat, proteins, lactose) were studied by electrochemical method with a Lactostar analyzer Funke Gerber type specialized for goat milk. Milk fatty acids profile, as fatty acids methyl esters (FAME), was determined by chromatographically gas method. The considerable high protein content found in half breeds, might be explained by the fact that bucks from specialized breeds such us Saanen and French Alpine which were used for half breeding, come from imported animals from France, which were locus genotyped for alpha S1 casein gene and were selected dominant genotypes that lead to a higher protein concentration in milk.The statistical analysis shows that the milk coming from Carpathian does and their half breeds is not significantly different regarding the levels of various fatty acids, saving omega 3 acids, which are considerable higher at Carpathian does, proving that food has the decisive role regarding composition.

Factors Affecting Milk Yield and Composition of Indigenous Balkan Goat Breed Reared in Semi Extensive Conditions

The aim of this study was to analyze effect of genetic and environmental factors on milk production traits of indigenous Balkan goat breed. The average milk yield of 150.43 kg in lactation that lasted 211.09 days was significantly influenced by flock and lactation, while average daily milk yield (0.724 kg) was additional significantly affected by stage of lactation (PÂ0.001). Variability of milk components content (fat, protein and solid nonfat – SNF) was under significant effect of flock and stage of lactation, interaction of these two factors and random effect of animal (PÂ0.001), while strain and lactation did not have significant effect on these traits (P&gt;0.05). Goats of AA genotype of alpha S1 casein had significantly higher fat, protein and SNF content than AF and FF genotype. These results provide important data that could be used as baseline for design of breeding program for improvement of production traits of Balkan goat breed.

Alpha S1-Casein Gene Polymorphısm in Nigerian Balami Sheep Breed Indigenous to Mubi

The study was conducted on five Balami sheep breed to determine and characterize the alpha S1 casein gene. Five blood samples were collected from each animal intravenously using sterile needle and syringe. The blood samples were placed in labelled tubes containing ethylene diamine tetraacetic acid (EDTA). The blood samples were transported in on ice cold chain container to the laboratory for analysis. Quick-DNA Miniprep TM kit used for DNA extraction and amplified using forward and reverse primers (CSN1S1F 5’-ACCCCTCAGGTACCCTAAGAAA-3’ and CSN1S1R 5’-GTTTATCCCCCACACTGCATTC-3’). The gene was sequenced and blasted against the NCBI database. Single nucleotide polymorphism analysis was performed to ascertain the variations. Multiple sequence alignment and phylogenetic analysis within and with the reference sequence was conducted online bioinformatics tools. Result from the analysis reveals that, the extracted DNA were found on chromosome 6, intron 16 and exon 17. The Balami breeds of sheep showed total number of polymorphic and monomorphic site of 68 and 600 respectively, and percentage of polymorphism of 10.18%. The Balami breed showed one amino acid substitution and genetic variation within breeds. Complete molecular characterization, genotyping and determination of allele frequency of alpha S1 gene in Balami breed of sheep indigenous to Nigeria and its variations is recommended for further research.

An 11-bp Indel Polymorphism within the CSN1S1 Gene Is Associated with Milk Performance and Body Measurement Traits in Chinese Goats.

Simple SummaryIn the field of animal breeding, selection using molecular genetic markers, such as insertions/deletions (indels), is a novel method to reduce the generation interval and more accurately improve performance. The casein alpha s1 (CSN1S1) gene is one of the major genes regulating the milk performance of mammals, and it is also relevant to body development. Previous studies have shown that an 11-bp indel in this gene was strongly associated with goat litter size, however, its effects on milk performance and body measurement traits have not been studied. In this study, this indel was genotyped in three Chinese goat breeds, and further analysis results revealed that this indel polymorphism was significantly associated with milk performance in dairy goats, as well as affecting the body measurement traits in all three breeds. These findings hint that the 11-bp indel within CSN1S1 gene could be utilized for effectively selecting goats with excellent performances in terms of production and breeding.The casein alpha s1 (CSN1S1) gene encodes α-s1 casein, one of the proteins constituting milk, which affects milk performance, as well as improving the absorption of calcium and bone development in mammals. A previous study found that an 11-bp insertion/deletion (indel) of this gene strongly affected litter size in goats. However, to our knowledge, the relationships between this polymorphism and the milk performance and body measurement traits of goats have not been reported. In this paper, the previously identified indel has been recognized in three Chinese goat breeds, namely the Guanzhong dairy goat (GZDG; n = 235), Shaanbei white cashmere goat (SBWC; n = 1092), and Hainan black goat (HNBG; n = 278), and the following three genotypes have been studied for all of the breeds: insertion/insertion (II), deletion/deletion (DD), and insertion/deletion (ID). The allele frequencies analyzed signified that the frequencies of the “D” allele were higher (47.8%–65.5%), similar to the previous report, which indicates that this polymorphism is genetically stable in different goat breeds. Further analysis showed that this indel was markedly associated with milk fat content, total solids content, solids-not-fat content, freezing point depression, and acidity in GZDG (p < 0.05), and also affected different body measurement traits in all three breeds (p < 0.05). The goats with II genotypes had superior milk performance, compared with the others; however, goats with DD genotypes had better body measurement sizes. Hence, it may be necessary to select goats with an II or DD genotype, based on the desired traits, while breeding. Our study provides information on the potential impact of the 11-bp indel polymorphism of the CSN1S1 gene for improving the milk performance and body measurement traits in goats.

L-Lactate Dehydrogenase B Chain Associated with Milk Protein Content in Dairy Cows.

Simple SummaryThe aim of this study was to explore the genes associated with milk protein content in dairy cows. Seven down-regulated and three up-regulated proteins were found in isolated milk epithelial cells (MECs) from dairy cows with high milk protein level (group High). l-leucine depletion not only decreased the proteins synthesis (p < 0.05), but also decreased l-lactate dehydrogenase B chain (LDH-B) mRNA expression in bovine mammary alveolar cells MAC-T cells (p < 0.05). This study suggested that LDH-B is negatively associated with the milk protein content of dairy cows and has a positive relationship with l-leucine. These findings may provide some theoretical basis to study individual differences in the milk protein synthesis ability of dairy cows.This study aimed to explore genes associated with milk protein content in dairy cows and their relationships with l-leucine. Ten primiparous Holstein cows (93.8 ± 11.56 milking days) fed the same diet were divided into two groups depending on their milk protein contents (group High, 3.34 ± 0.10%; and group Low, 2.86 ± 0.05%). Milk epithelial cells (MECs) were isolated from the collected morning milk and differentially expressed proteins in MECs were explored by two-dimensional gel electrophoresis (2-DE). Then, the mRNA expression of these proteins was detected by real time PCR in MAC-T cells incubated with three different media named positive control (PC), negative control (NC), and l-leucine depletion (NO-leu). Results showed that ten proteins were differentially expressed in MECs from cows in group High. They included seven down-regulated ones (heat shock protein beta-1 (HSPB1), 78 kDa glucose-regulated protein (GRP-78), l-lactate dehydrogenase B chain (LDH-B), malate dehydrogenase, cytoplasmic (MDH1), annexin I (ANXA1), cytokeratin-7 (CK-7), and glyceraldehyde-3-phosphate dehydrogenase (GAPDH)), and three up-regulated ones (prohibitin (PHB), beta casein (CSN2), and alpha S1 casein (CSN1S1)). When l-leucine was depleted from the medium, not only proteins content was lowered (p < 0.05), but also the LDH-B mRNA expression was decreased in MAC-T cells (p < 0.05). In conclusion, LDH-B is negatively associated with the milk protein content of dairy cows and has a positive association with l-leucine.

Aлмaты oблыcы түйeлepiндe csn3 гeнiнiң тapaлy жиiлiгi

Camel breeding is the important industry of agriculture which provides the food and light industry with milk, wool, leather, etc. products. Especially, shubat obtained from camel milk due to its special taste and medical properties is in great demand in the market. In this way, in order to improve the breeding of camels in the dairy direction, it is very important to carry out selection work in this direction. The total amount of caseins that make up camel milk is about 75% of milk protein. These caseins consist of four fractions encoded by the genes CSN1S1, CSN1S2, CSN2 and CSN3: alpha s1, alpha s2, beta and κ-casein. Genetic polymorphism of the above-mentioned genes determines the quantitative and technological properties of milk. Propagation of homozygous animals by these genes is carried out in order to improve the qualitative properties of milk, namely fat content and nutrition. The most beneficial and affordable method for studying these genes is the PCR-RFLP method. In this work, there was studied the polymorphism of the CSN3 gene, which is involved in the formation of qualitative traits of milk in several two-humped camel (Camelus bactrianus) populations that are bred in farms of the Almaty region. Among the 53 camels selected for study, the «useful» cytosine frequency is 0.39. As well, among the studied populations, Hardy-Weinberg equlibrium was determined by the distribution of genotypes (χ2 = 12.1). Key words: camels, dairy productivity, kappa casein, PCR-RFLP analysis.

EFFECTS OF ALPHA-S1-CASEIN TRYPTIC HYDROLYSATE AND L-THEANINE ON SLEEP DISORDER AND PSYCHOLOGICAL COMPONENTS: A RANDOMIZED, DOUBLE-BLIND, PLACEBO-CONTROLLED STUDY

Sleep disorder is common among the general population. A nutritional supplement containing alpha-s1-casein tryptic hydrolysate and L-theanine was evaluated for its effects in improving sleep quality. The study was conducted using a double-blind randomized trial. Intervention group received once-daily capsules of 150 mg alpha s1 casein tryptic hydrolysate and 50 mg L-theanine, and the control group were given placebo (150 mg skimmed milk powder) for four weeks. The outcome measurements were assessed on weekly basis using PSQI, DASS-21, clinical and biochemical parameters. ANOVA test were used to assess within group differences and ANCOVA were used to check for differences between groups. Significantly lower (better) sleep latency score, sleep disturbances score and daytime dysfunction score were demonstrated on week-4 in intervention group compared to placebo group. Profound differences were observed between the two groups for anxiety and stress scores from week-3 onwards, in which lower anxiety and stress scores were observed in intervention group compared to placebo group. In addition, significantly lower depression score in intervention group compared to placebo group on week-4 was observed. Intervention supplement has demonstrated potent effects in relieving anxiety, stress, depression and sleep quality.